// ==========================================================
// Kodak PhotoCD Loader
//
// Design and implementation by
// - Floris van den Berg (flvdberg@wxs.nl)
//
// Based on pascal code developed by Alex Kwak
//
// This file is part of FreeImage 3
//
// COVERED CODE IS PROVIDED UNDER THIS LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTY
// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES
// THAT THE COVERED CODE IS FREE OF DEFECTS, MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE
// OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE COVERED
// CODE IS WITH YOU. SHOULD ANY COVERED CODE PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT
// THE INITIAL DEVELOPER OR ANY OTHER CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY
// SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL
// PART OF THIS LICENSE. NO USE OF ANY COVERED CODE IS AUTHORIZED HEREUNDER EXCEPT UNDER
// THIS DISCLAIMER.
//
// Use at your own risk!
// ==========================================================

#include "FreeImage.h"
#include "Utilities.h"

// ==========================================================
// Internal functions
// ==========================================================

static int
clamp(double x) {
    int a = (int)floor(x + 0.5);
    return (a < 0) ? 0 : (a > 255) ? 255 : a;
}

static void
YUV2RGB(int y, int cb, int cr, int &r, int &g, int &b) {
    double c11 = 0.0054980  * 256.0;
    double c12 = 0.0000001  * 256.0;
    double c13 = 0.0051681  * 256.0;
    double c21 = 0.0054980  * 256.0;
    double c22 = -0.0015446 * 256.0;
    double c23 = -0.0026325 * 256.0;
    double c31 = 0.0054980  * 256.0;
    double c32 = 0.0079533  * 256.0;
    double c33 = 0.0000001  * 256.0;

    r = clamp(c11 * y + c12 * (cb - 156) + c13 * (cr - 137));
    g = clamp(c21 * y + c22 * (cb - 156) + c23 * (cr - 137));
    b = clamp(c31 * y + c32 * (cb - 156) + c33 * (cr - 137));
}

static BOOL
VerticalOrientation(FreeImageIO *io, fi_handle handle) {
    char buffer[128];

    io->read_proc(buffer, 128, 1, handle);

    return (buffer[72] & 63) == 8;
}

// ==========================================================
// Plugin Interface
// ==========================================================

static int s_format_id;

// ==========================================================
// Plugin Implementation
// ==========================================================

static const char * DLL_CALLCONV
Format() {
    return "PCD";
}

static const char * DLL_CALLCONV
Description() {
    return "Kodak PhotoCD";
}

static const char * DLL_CALLCONV
Extension() {
    return "pcd";
}

static const char * DLL_CALLCONV
RegExpr() {
    return NULL;
}

static const char * DLL_CALLCONV
MimeType() {
    return "image/x-photo-cd";
}

static BOOL DLL_CALLCONV
SupportsExportDepth(int depth) {
    return FALSE;
}

static BOOL DLL_CALLCONV
SupportsExportType(FREE_IMAGE_TYPE type) {
    return FALSE;
}

static BOOL DLL_CALLCONV
SupportsNoPixels() {
    return TRUE;
}

// ----------------------------------------------------------

static FIBITMAP * DLL_CALLCONV
Load(FreeImageIO *io, fi_handle handle, int page, int flags, void *data) {
    FIBITMAP *dib = NULL;
    unsigned width;
    unsigned height;
    const unsigned bpp = 24;
    int scan_line_add   = 1;
    int start_scan_line = 0;

    BYTE *y1 = NULL, *y2 = NULL, *cbcr = NULL;

    BOOL header_only = (flags & FIF_LOAD_NOPIXELS) == FIF_LOAD_NOPIXELS;

    // to make absolute seeks possible we store the current position in the file

    long offset_in_file = io->tell_proc(handle);
    long seek = 0;

    // decide which bitmap in the cabinet to load

    switch (flags) {
        case PCD_BASEDIV4 :
            seek = 0x2000;
            width = 192;
            height = 128;
            break;

        case PCD_BASEDIV16 :
            seek = 0xB800;
            width = 384;
            height = 256;
            break;

        default :
            seek = 0x30000;
            width = 768;
            height = 512;
            break;
    }

    try {
        // allocate the dib and write out the header
        dib = FreeImage_AllocateHeader(header_only, width, height, bpp, FI_RGBA_RED_MASK, FI_RGBA_GREEN_MASK, FI_RGBA_BLUE_MASK);
        if(!dib) throw FI_MSG_ERROR_DIB_MEMORY;

        if(header_only) {
            return dib;
        }

        // check if the PCD is bottom-up

        if (VerticalOrientation(io, handle)) {
            scan_line_add = -1;
            start_scan_line = height - 1;
        }

        // temporary stuff to load PCD

        BYTE *y1 = (BYTE*)malloc(width * sizeof(BYTE));
        BYTE *y2 = (BYTE*)malloc(width * sizeof(BYTE));
        BYTE *cbcr = (BYTE*)malloc(width * sizeof(BYTE));
        if(!y1 || !y2 || !cbcr) throw FI_MSG_ERROR_MEMORY;

        BYTE *yl[] = { y1, y2 };

        // seek to the part where the bitmap data begins

        io->seek_proc(handle, offset_in_file, SEEK_SET);
        io->seek_proc(handle, seek, SEEK_CUR);

        // read the data

        for (unsigned y = 0; y < height / 2; y++) {
            io->read_proc(y1, width, 1, handle);
            io->read_proc(y2, width, 1, handle);
            io->read_proc(cbcr, width, 1, handle);

            for (int i = 0; i < 2; i++) {
                BYTE *bits = FreeImage_GetScanLine(dib, start_scan_line);
                for (unsigned x = 0; x < width; x++) {
                    int r, g, b;

                    YUV2RGB(yl[i][x], cbcr[x / 2], cbcr[(width / 2) + (x / 2)], r, g, b);

                    bits[FI_RGBA_BLUE]  = (BYTE)b;
                    bits[FI_RGBA_GREEN] = (BYTE)g;
                    bits[FI_RGBA_RED]   = (BYTE)r;
                    bits += 3;
                }

                start_scan_line += scan_line_add;
            }
        }

        free(cbcr);
        free(y2);
        free(y1);

        return dib;

    } catch(const char *text) {
        if(dib) FreeImage_Unload(dib);
        if(cbcr) free(cbcr);
        if(y2) free(y2);
        if(y1) free(y1);

        FreeImage_OutputMessageProc(s_format_id, text);

        return NULL;
    }
}

// ==========================================================
//   Init
// ==========================================================

void DLL_CALLCONV
InitPCD(Plugin *plugin, int format_id) {
    s_format_id = format_id;

    plugin->format_proc = Format;
    plugin->description_proc = Description;
    plugin->extension_proc = Extension;
    plugin->regexpr_proc = RegExpr;
    plugin->open_proc = NULL;
    plugin->close_proc = NULL;
    plugin->pagecount_proc = NULL;
    plugin->pagecapability_proc = NULL;
    plugin->load_proc = Load;
    plugin->save_proc = NULL;
    plugin->validate_proc = NULL;
    plugin->mime_proc = MimeType;
    plugin->supports_export_bpp_proc = SupportsExportDepth;
    plugin->supports_export_type_proc = SupportsExportType;
    plugin->supports_icc_profiles_proc = NULL;
    plugin->supports_no_pixels_proc = SupportsNoPixels;
}
